#include <stdio.h>
#include <stdlib.h>
char get_choice(void);
char get_first(void);
int get_int(void);
void count(void);
int main(void)
{
    int choice;
    void count(void);
    while((choice = get_choice()) != 'q')
    {
        switch(choice)
        {
            case 'a': printf("Buy low, sell high.\n");  break;
            case 'b': putchar('\a'); break;
            case 'c': count(); break;
            default: printf("Program error.\n"); break;
        }
    }
    system("pause");
    printf("Bye.\n");
    return 0;
}


void count(void)
{
    int n, i;
    printf("Count how far? Enter an integer: \n");
    n = get_int();
    for(i = 1; i <= n; i++)
    {
        printf("%d\n", i);
    }
    while(getchar() != '\n')
        continue;
}

char get_choice(void)
{
    int ch;
    printf("Enter the letter of you choice: \n");
    printf("a.advice        b.bell\n");
    printf("c.count         d.quit\n");
    ch = get_first();
    while((ch < 'a' || ch > 'c') && ch != 'q')
    {
        printf("Please respond with a, b, c, or q.\n");
        ch = get_first();
    }
    return ch;
}

char get_first(void)
{
    int ch;
    ch = getchar();
    while(getchar() != '\n')
        continue;
    return ch;
}

int get_int(void)
{
    int input;
    char ch;
    while(scanf("%d", &input) != 1)
    {
        while((ch = getchar()) != '\n')
            putchar(ch);
        printf(" is not an integer.\nPlease enter an ");
        printf("integer value, such as 25, -178, or 3: ");
    }
    return input;
}
